Fiberglass shingles are a popular roofing choice due to their durability and cost-effectiveness, but like many roofing materials, they rely heavily on proper flashing to prevent leaks, especially around chimneys. Chimney flashing is the metal barrier placed where the roof meets the chimney to create a waterproof seal. Leaks often happen when this flashing is improperly installed, damaged, or corroded over time. Water can seep through cracks in the flashing or where the shingles meet the flashing, leading to water stains on ceilings or walls and potentially more serious structural damage. Simple DIY checks include inspecting the area around your chimney for cracked or lifted shingles, rusted or loose flashing, and any gaps where light shines through inside your attic. You can also carefully check after rain for active drips near the chimney. These early signs alert you to a possible flashing issue before it worsens.
Because chimney flashing involves crucial waterproofing elements and can be complex to replace correctly, it’s wise to call a professional roofer if you suspect a leak. A good roofer will evaluate any flashing damage, check for proper installation, and inspect surrounding shingles for issues that might cause leaks. When consulting a contractor, ask directly, “How will you ensure the flashing around the chimney is sealed and sealed in a way that meets the shingle manufacturer’s warranty requirements?” and “What flashing materials and sealants do you recommend for long-lasting protection with fiberglass shingles?” These questions help ensure the roofer follows best practices and codes, protecting your home and your shingle warranty. Avoid quick fixes with generic tar that may void warranties or hide problems that need real repairs.